Polarization　curve　and　electrochemical　impedance　spectroscopy　(EIS)　tests　were　applied　to　investigate　the　corrosion　behaviors　and　corrosion　kinetics　of　spark　plasma　sintering　NdFeB　magnets　in　different　electrolytes.　The　results　show　that　in　alkaline　solution　the　electrochemical　reaction　of　the　magnets　is　controlled　by　the　step　of　surface　charge　transfer　i.e.　activation　polarization　process,　the　magnet　with　a　compact　passivation　layer　on　their　surface　exhibits　evident　passive　behavior　in　this　circumstance;　in　weak　acid　solution,　the　electrochemical　reaction　of　the　magnets　is　controlled　by　the　step　of　active　substances　adsorption　process,　the　magnet　is　susceptible　to　corrosion　in　this　environment　since　there　are　many　active　reaction　channels　in　the　anodic　(Nd-rich　phase)　areas.　Compared　with　conventional　sintered　NdFeB　magnet,　SPS　NdFeB　magnet　possesses　excellent　corrosion　resistance.